Honestly, keep it simple. Spatchcock method is great for a whole chicken. Don't worry about searing, reverse searing, slide and searing, sear and slide, none of it. Just oil up the skin and hit it with your rub/herbs, put it on indirect with the grill running 350-400 and let it go indirect the entire time. Pull it off at 160 and let it rest to 165.
The last few I've done I didn't have any olive oil so I sprayed PAM all over the skin then did my salt, pepper, and rosemary. The skin was very crispy.
Forgot about the fire. I usually light a whole chimney and throw it in the Slow n Sear. I place a drip pan under the chicken to catch all the fat and keep the kettle clean. If I do any smoke wood I'll use peach or pecan and only one chunk of it. Poultry takes the smoke very easily. No water in the pan or in the SnS